Compiler Error C3850

'char': a universal-character-name specifies an invalid character

Characters represented as universal character names must represent valid Unicode code points in the range 0-10FFFF. A universal character name cannot contain a value in the Unicode surrogate range, D800-DFFF, or an encoded surrogate pair. The compiler generates the surrogate pair from a valid code point automatically.

In code compiled as C, a universal character name may not represent a character in the range 0000-009F, inclusive, with the exceptions of 0024 ('$'), 0040 ('@') and 0060 ('`').

In code compiled as C++, a universal character name may use any valid Unicode code point in a string or character literal. Outside of a literal, a universal character name may not represent a control character in the ranges 0000-001F or 007F-009F, both inclusive, or a member of the basic source character set. For more information, see Character Sets.

The following sample generates C3850, and shows how to fix it:

// C3850.cpp
int main() {
   int \u0019 = 0;   // C3850, not in allowed range for an identifier
   const wchar_t * wstr_bad  = L"\UD840DC8A"; // C3850, UCN is surrogate pair
   const wchar_t * wstr_good = L"\U0002008A"; // Okay, UCN is valid code point
}